Answer
From top to bottom: b, c, a, b, d
Work Step by Step
The lag phase is always at the beginning of the curve, since it is a stage of adaptation and the beginning of cell growth.
The next phase is where the exponential growth happens (each cell divides and results in two daughter cells). In this stage the speed of growth is the highest (log phase).
Cells then begin to die, while others continue to divide (phase c in the curve). This deterioration is prolonged as nutrients begin to become scarce and unwanted metabolites and dead cells begin to accumulate in the medium. At this stage, most cells can no longer grow, and the number of living cells begins to decline.
